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1.
Int J Mol Sci ; 25(13)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39000362

RESUMO

Exposure to microgravity during spaceflight induces the alterations in endothelial cell function associated with post-flight cardiovascular deconditioning. PIEZO1 is a major mechanosensitive ion channel that regulates endothelial cell function. In this study, we used a two-dimensional clinostat to investigate the expression of PIEZO1 and its regulatory mechanism on human umbilical vein endothelial cells (HUVECs) under simulated microgravity. Utilizing quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot analysis, we observed that PIEZO1 expression was significantly increased in response to simulated microgravity. Moreover, we found microgravity promoted endothelial cells migration by increasing expression of PIEZO1. Proteomics analysis highlighted the importance of C-X-C chemokine receptor type 4(CXCR4) as a main target molecule of PIEZO1 in HUVECs. CXCR4 protein level was increased with simulated microgravity and decreased with PIEZO1 knock down. The mechanistic study showed that PIEZO1 enhances CXCR4 expression via Ca2+ influx. In addition, CXCR4 could promote endothelial cell migration under simulated microgravity. Taken together, these results suggest that the upregulation of PIEZO1 in response to simulated microgravity regulates endothelial cell migration due to enhancing CXCR4 expression via Ca2+ influx.


Assuntos
Movimento Celular , Células Endoteliais da Veia Umbilical Humana , Canais Iônicos , Receptores CXCR4 , Simulação de Ausência de Peso , Receptores CXCR4/metabolismo , Receptores CXCR4/genética , Humanos , Canais Iônicos/metabolismo , Canais Iônicos/genética , Movimento Celular/genética , Células Endoteliais da Veia Umbilical Humana/metabolismo , Cálcio/metabolismo , Células Endoteliais/metabolismo , Regulação da Expressão Gênica
2.
Apoptosis ; 25(1-2): 73-91, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31768842

RESUMO

Weightlessness-induced cardiovascular dysfunction can lead to physiological and pathological consequences. It has been shown that spaceflight or simulated microgravity can alter expression profiles of some microRNAs (miRNAs). Here, we attempt to identify the role of miRNAs in human umbilical vein endothelial cells (HUVECs) apoptosis under simulated microgravity. RNA-sequencing and quantitative real-time PCR (qRT-PCR) assays were used to identify differentially expressed miRNAs in HUVECs under simulated microgravity. Then we obtained the target genes of these miRNAs through target analysis software. Moreover, GO and KEGG enrichment analysis were performed. The effects of these miRNAs on HUVECs apoptosis were evaluated by flow cytometry, Western blot and Hoechst staining. Furthermore, we obtained the target gene of miR-27b-5p by luciferase assay, qRT-PCR and Western blot. Finally, we investigated the relationship between this target gene and miR-27b-5p in HUVECs apoptosis under normal gravity or simulated microgravity. We found 29 differentially expressed miRNAs in HUVECs under simulated microgravity. Of them, the expressions of 3 miRNAs were validated by qRT-PCR. We demonstrated that miR-27b-5p affected HUVECs apoptosis by inhibiting zinc fingers and homeoboxes 1 (ZHX1). Our results reported here demonstrate for the first time that simulated microgravity can alter the expression of some miRNAs in HUVECs and miR-27b-5p may protect HUVECs from apoptosis under simulated microgravity by targeting ZHX1.


Assuntos
Apoptose , Células Endoteliais da Veia Umbilical Humana/citologia , Ausência de Peso/efeitos adversos , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Células Endoteliais da Veia Umbilical Humana/química , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
3.
Apoptosis ; 24(9-10): 812-825, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31359205

RESUMO

Astronauts exposed to a gravity-free environment experience cardiovascular deconditioning that causes post-spaceflight orthostatic intolerance and other pathological conditions. Endothelial dysfunction is an important factor responsible for this alteration. Our previous study showed enhanced autophagy in endothelial cells under simulated microgravity. The present study explored the cytoprotective role of autophagy under microgravity in human umbilical vein endothelial cells (HUVECs). We found that clinorotation for 48 h induced apoptosis and endoplasmic reticulum (ER) stress in HUVECs. ER stress and the unfolded protein response (UPR) partially contributed to apoptosis under clinorotation. Autophagy partially reduced ER stress and restored UPR signaling by autophagic clearance of ubiquitin-protein aggregates, thereby reducing apoptosis. In addition, the ER stress antagonist 4-phenylbutyric acid upregulated autophagy in HUVECs. Taken together, these findings indicate that autophagy plays a protective role against apoptosis under clinorotation by clearing protein aggregates and partially restoring the UPR.


Assuntos
Apoptose , Gravidade Alterada/efeitos adversos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Fenilbutiratos/farmacologia , Autofagia/efeitos dos fármacos , Linhagem Celular , Estresse do Retículo Endoplasmático , Humanos , Substâncias Protetoras/farmacologia , Rotação/efeitos adversos , Resposta a Proteínas não Dobradas
4.
Cell Physiol Biochem ; 41(1): 227-238, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28214845

RESUMO

BACKGROUND/AIMS: Microgravity leads to hydrodynamic alterations in the cardiovascular system and is associated with increased angiogenesis, an important aspect of endothelial cell behavior to initiate new vessel growth. Given the critical role of Rho GTPase-dependent cytoskeleton rearrangement in cell migration, small GTPase RhoA might play a potential role in microgravity-induced angiogenesis. METHODS: We examined the organization of actin filaments by FITC-conjugated phalloidin staining, as well as the expression and activity of RhoA by quantitative PCR and Western blot, in human umbilical vein endothelial cells (HUVECs) under normal gravity and simulated microgravity. Effect of simulated microgravity on the wound closure and tube formation in HUVECs, and their dependence on RhoA, were also analyzed by cell migration and tube formation assays. RESULTS: We show that in HUVECs actin filaments are disorganized and RhoA activity is reduced by simulated microgravity. Blocking RhoA activity either by C3 transferase Rho inhibitor or siRNA knockdown mimicked the effect of simulated microgravity on inducing actin filament disassembly, followed by enhanced wound closure and tube formation in HUVECs, which closely resembled effects seen on microgravity-treated cells. In contrast, overexpressing RhoA in microgravity-treated HUVECs restored the actin filaments, and decreased wound closure and tube formation abilities. CONCLUSION: These results suggest that RhoA inactivation is involved in the actin rearrangement-associated angiogenic responses in HUVECs during simulated microgravity.


Assuntos
Citoesqueleto de Actina/fisiologia , Actinas/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Neovascularização Fisiológica/fisiologia , Proteína rhoA de Ligação ao GTP/metabolismo , Movimento Celular , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Microscopia de Fluorescência , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Simulação de Ausência de Peso , Proteína rhoA de Ligação ao GTP/antagonistas & inibidores , Proteína rhoA de Ligação ao GTP/genética
5.
Cell Physiol Biochem ; 38(2): 502-13, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26828798

RESUMO

BACKGROUND/AIMS: The potential role of caveolin-1 in modulating angiogenesis in microgravity environment is unexplored. METHODS: Using simulated microgravity by clinostat, we measured the expressions and interactions of caveolin-1 and eNOS in human umbilical vein endothelial cells. RESULTS: We found that decreased caveolin-1 expression is associated with increased expression and phosphorylation levels of eNOS in endothelial cells stimulated by microgravity, which causes a dissociation of eNOS from caveolin-1 complexes. As a result, microgravity induces cell migration and tube formation in endothelial cell in vitro that depends on the regulations of caveolin-1. CONCLUSION: Our study provides insight for the important endothelial functions in altered gravitational environments.


Assuntos
Cavéolas/metabolismo , Caveolina 1/metabolismo , Neovascularização Fisiológica , Óxido Nítrico Sintase Tipo III/metabolismo , Simulação de Ausência de Peso , Caveolina 1/análise , Movimento Celular , Células Endoteliais da Veia Umbilical Humana , Humanos , Óxido Nítrico Sintase Tipo III/análise , Mapas de Interação de Proteínas
6.
Biochem Biophys Res Commun ; 460(2): 327-32, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25804637

RESUMO

Data from human and rodent studies have demonstrated that microgravity induces observed bone loss in real spaceflight or simulated experiments. The decrease of bone formation and block of maturation may play important roles in bone loss induced by microgravity. The aim of this study was to investigate the changes of proliferation and differentiation in bone marrow mesenchymal stem cells (BMSCs) induced by simulated microgravity and the mechanisms underlying it. We report here that clinorotation, a simulated model of microgravity, decreased proliferation and differentiation in BMSCs after exposure to 48 h simulated microgravity. The inhibited proliferation are related with blocking the cell cycle in G2/M and enhancing the apoptosis. While alterations of the osteoblast differentiation due to the decreased SATB2 expression induced by simulated microgravity in BMSCs.


Assuntos
Células da Medula Óssea/citologia , Diferenciação Celular , Proliferação de Células , Células-Tronco Mesenquimais/citologia , Animais , Sequência de Bases , Ciclo Celular , Linhagem Celular , Primers do DNA , Camundongos , Camundongos Endogâmicos C3H , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ausência de Peso
7.
Heliyon ; 10(2): e23973, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38293521

RESUMO

Purpose: This study assessed the moderating effect of gender on the indirect effects of positive and negative parenting styles on Internet addiction through interpersonal relationship problem. Methods: A cross-sectional survey of randomly sampled 1194 college students recruited voluntarily from three universities in China was conducted to assess the variables of positive and negative parenting styles, interpersonal relationship problem, and Internet addiction. Results: Positive parenting style, such as emotional warmth, was a protective factor for the development of Internet addiction, whereas negative parenting style, such as rejection and overprotection, was a potential risk factor for Internet addiction. Furthermore, interpersonal relationship problem completely mediated the association between positive parenting style and Internet addiction but partially mediated the relationship between negative parenting style and Internet addiction. Finally, gender moderated the indirect effect of parenting style on Internet addiction through interpersonal relationship problem. Conclusion: The correlation between positive parenting style and interpersonal relationship problem was considerably weaker among females, whereas the association between interpersonal relationship problem and Internet addiction was much stronger among females. For the prevention and intervention of Internet addiction, it is important to increase positive parenting style for males while enhancing interpersonal skills training for females. Further longitudinal studies should discuss the effects of paternal and maternal parenting styles on Internet addiction.

8.
Biochem Cell Biol ; 91(5): 309-14, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24032680

RESUMO

Individuals exposed to extended periods of spaceflight or prolonged 6° head-down-tilt bed rest often suffer from health hazards represented by cardiovascular deconditioning. Many studies have reported that alterations in vascular endothelial cells contribute to cardiovascular dysfunction induced by microgravity. Autophagy, a lysosomal degradation pathway, serves an adaptive role for survival, differentiation, and development in cellular homeostasis, and can be triggered by various environmental stimuli. However, whether autophagy can be induced in endothelial cells by real or simulated microgravity remains to be determined. This study was designed to investigate the effects of simulated microgravity on the activation of autophagy in human umbilical vein endothelial cells (HUVECs). We report here that clinorotation, a simulated model of microgravity, enhances autophagosome formation, increases LC3 and beclin-1 expression, and promotes the conversion of LC3-I to LC3-II in HUVECs. These results demonstrate that simulated microgravity for 48 h activates autophagy of vascular endothelial cells.


Assuntos
Autofagia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Rotação/efeitos adversos , Ausência de Peso/efeitos adversos , Proteínas Reguladoras de Apoptose/biossíntese , Proteína Beclina-1 , Descondicionamento Cardiovascular/fisiologia , Linhagem Celular , Humanos , Proteínas de Membrana/biossíntese , Proteínas Associadas aos Microtúbulos/biossíntese , Proteínas Associadas aos Microtúbulos/metabolismo , Voo Espacial
9.
Europace ; 15(1): 127-34, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22791300

RESUMO

AIMS: Orthostatic intolerance (OI) is a common clinical problem; however, effective and applicable clinical prevention/treatment is limited. The aim of this study was to investigate whether electroacupuncture (EA) is a novel effective treatment in attenuating OI in healthy individuals. METHODS AND RESULTS: This study used a randomized, controlled, crossover design using two protocols. Orthostatic intolerance was induced with a combination of head-up tilt (HUT) and lower body negative pressure (LBNP). Twenty healthy individuals in Protocol 1 and 10 healthy individuals in Protocol 2 received no EA, EA at PC-6 acupuncture points (acupoint), and EA at a non-acupoint in a random order with an interim of 1 week. Electroacupuncture was administered prior to HUT/LBNP in Protocol 1 and simultaneously during HUT/LBNP in Protocol 2. Electroacupuncture at PC-6 administered either before or during HUT/LBNP postponed the occurrence of pre-syncopal symptoms, improved haemodynamic responses to HUT/LBNP (including increased diastolic blood pressure, stroke volume, and total peripheral resistance and a decreased heart rate), blunted decreases of maximum velocity and velocity time integral of blood flow in the middle cerebral artery, and increased plasma noradrenalin and adrenalin concentrations. In addition, heart rate variability analysis revealed that EA at PC-6 either before or during HUT/LBNP decreased high-frequency ranges of R-R interval while increasing low-frequency ranges of R-R interval, which indicates an elevated heart sympathetic tone. CONCLUSION: Electroacupuncture at PC-6 is effective in improving orthostatic tolerance. Cardiac function improvement and sympathetic activation are responsible for the improved orthostatic tolerance after EA. EA represents a novel intervention against OI.


Assuntos
Eletroacupuntura/métodos , Intolerância Ortostática/fisiopatologia , Intolerância Ortostática/reabilitação , Sistema Nervoso Simpático/fisiopatologia , Disfunção Ventricular Esquerda/prevenção & controle , Disfunção Ventricular Esquerda/fisiopatologia , Feminino , Humanos , Masculino , Intolerância Ortostática/complicações , Valores de Referência , Resultado do Tratamento , Disfunção Ventricular Esquerda/etiologia , Adulto Jovem
10.
Bone Res ; 11(1): 53, 2023 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-37872163

RESUMO

Bone marrow mesenchymal stem cell (BMSC) osteogenic differentiation and osteoblast function play critical roles in bone formation, which is a highly regulated process. Long noncoding RNAs (lncRNAs) perform diverse functions in a variety of biological processes, including BMSC osteogenic differentiation. Although several studies have reported that HOX transcript antisense RNA (HOTAIR) is involved in BMSC osteogenic differentiation, its effect on bone formation in vivo remains unclear. Here, by constructing transgenic mice with BMSC (Prx1-HOTAIR)- and osteoblast (Bglap-HOTAIR)-specific overexpression of HOTAIR, we found that Prx1-HOTAIR and Bglap-HOTAIR transgenic mice show different bone phenotypes in vivo. Specifically, Prx1-HOTAIR mice showed delayed bone formation, while Bglap-HOTAIR mice showed increased bone formation. HOTAIR inhibits BMSC osteogenic differentiation but promotes osteoblast function in vitro. Furthermore, we identified that HOTAIR is mainly located in the nucleus of BMSCs and in the cytoplasm of osteoblasts. HOTAIR displays a nucleocytoplasmic translocation pattern during BMSC osteogenic differentiation. We first identified that the RNA-binding protein human antigen R (HuR) is responsible for HOTAIR nucleocytoplasmic translocation. HOTAIR is essential for osteoblast function, and cytoplasmic HOTAIR binds to miR-214 and acts as a ceRNA to increase Atf4 protein levels and osteoblast function. Bglap-HOTAIR mice, but not Prx1-HOTAIR mice, showed alleviation of bone loss induced by unloading. This study reveals the importance of temporal and spatial regulation of HOTAIR in BMSC osteogenic differentiation and bone formation, which provides new insights into precise regulation as a target for bone loss.


Assuntos
MicroRNAs , RNA Longo não Codificante , Animais , Humanos , Camundongos , Osso e Ossos/metabolismo , Diferenciação Celular/genética , Camundongos Transgênicos , MicroRNAs/genética , Osteogênese/genética , RNA Longo não Codificante/genética
11.
Front Neurosci ; 17: 1216998, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38125401

RESUMO

Objective: Vestibular provocation is one of the main causes of flight illusions, and its occurrence is closely related to the susceptibility of motion sickness (MS). However, existing training programs have limited effect in improving the resistance to motion sickness. In this study, we investigated the effects of hypoxia acclimatization training (HAT) on the resistance to motion sickness. Methods: Healthy military college students were identified as subjects according to the criteria. MS model was induced by a rotary chair. Experimental groups included control, HAT, 3D roller training (3DRT), and combined training. Results: The Graybiel scores were decreased in the HAT group and the 3DRT group and further decreased in the combined training group in MS induced by the rotary chair. Participants had a significant increase in blood pressure after the rotary chair test and a significant increase in the heart rate during the rotary chair test, but these changes disappeared in all three training groups. Additionally, LFn was increased, HFn was decreased, and LF/HF was increased accordingly during the rotary chair test in the control group, but the changes of these three parameters were completely opposite in the three training groups during the rotary chair test. Compared with the control group, the decreasing changes in pupillary contraction velocity (PCV) and pupillary minimum diameter (PMD) of the three training groups were smaller. In particular, the binocular PCV changes were further attenuated in the combined training group. Conclusion: Our research provides a possible candidate solution for training military pilots in the resistance to motion sickness.

12.
Eur J Appl Physiol ; 112(4): 1295-305, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21786130

RESUMO

Changes of venous compliance may contribute in part to postflight orthostatic intolerance. The purpose of the present study was to determine whether intermittent artificial gravity exposure with ergometric exercise could prevent venous compliance changes in the lower limbs due to simulated weightlessness. Twelve healthy male volunteers were exposed to simulated microgravity for 4 days of head-down bed rest (HDBR). Six subjects were randomly loaded 1.0-2.0 Gz intermittent artificial gravity (at foot level) with 40 W of ergometric workload every day (countermeasure group, CM). The six others served as the control (CON group). Venous compliance was estimated by measuring the corresponding change of cross-sectional area (CSA) of popliteal vein at each minute of various venous occlusion pressure stages. Basal CSA was significantly lower after bed rest in the control group, and preserved in the countermeasure group. The percent increase in the CSA of CON group was significantly greater almost at each minute of various venous cuff pressures after bed rest than before. Compliance of popliteal vein of CON group was significant greater when 40, 60 and 80 mmHg cuff pressure applied after bed rest than before of CON group. In conclusions, a 4-day simulated weightlessness leads to increase of popliteal venous compliance; centrifuge-induced artificial gravity with ergometric exercise can prevent enhancement of popliteal venous compliance due to 4-day head-down tilt bed rest, the effect of the countermeasure on compliance might involve changes in venous filling and changes in venous structure.


Assuntos
Repouso em Cama/efeitos adversos , Terapia por Exercício , Gravidade Alterada , Decúbito Inclinado com Rebaixamento da Cabeça/efeitos adversos , Intolerância Ortostática/prevenção & controle , Veia Poplítea/fisiopatologia , Análise de Variância , Pressão Sanguínea , China , Complacência (Medida de Distensibilidade) , Ergometria , Frequência Cardíaca , Humanos , Masculino , Intolerância Ortostática/diagnóstico por imagem , Intolerância Ortostática/etiologia , Intolerância Ortostática/fisiopatologia , Veia Poplítea/diagnóstico por imagem , Fatores de Tempo , Ultrassonografia , Simulação de Ausência de Peso , Adulto Jovem
13.
Mil Med ; 177(2): 163-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22360061

RESUMO

A questionnaire survey was performed for the first time to assess the prevalence of visual symptoms and G-induced loss of consciousness (G-LOC) due to +Gz exposure in the Chinese Air Force (CAF) to determine the effectiveness of current G tolerance training. Responses were received from 594 individuals. Among them, 302 reported at least one episode of some sort of symptoms related to +Gz, including 110 (18.5%) with visual blurring, 231 (38.9%) with greyout, 111 (18.7%) with blackout, and 49 (8.2%) with G-LOC. Incidences were most common in aircrew with 250-1,000 flying hours (53.6%) and were more prevalent in those with fewer on type flying hours (p < 0.001). The most common situation was reported between +5 and 5.9 Gz. The results indicate a fairly high prevalence of visual symptoms and G-LOC among Chinese Air Force aircrew. There remains considerable scope for +Gz education, particularly in the early centrifuge training and selection of rational physical exercises.


Assuntos
Aviação , Hipergravidade/efeitos adversos , Transtornos da Visão/epidemiologia , Transtornos da Visão/etiologia , Adulto , Medicina Aeroespacial , China/epidemiologia , Gravitação , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Militares , Inquéritos e Questionários , Inconsciência/epidemiologia , Inconsciência/etiologia , Acuidade Visual , Adulto Jovem
14.
Front Cell Dev Biol ; 10: 896014, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35874841

RESUMO

The effect of cardiovascular dysfunction including orthostatic intolerance and disability on physical exercise is one of the health problems induced by long-term spaceflight astronauts face. As an important part of vascular structure, the vascular endothelium, uniquely sensitive to mechanical force, plays a pivotal role in coordinating vascular functions. Our study found that simulated microgravity induced PINK1-dependent mitophagy in human umbilical vein endothelial cells (HUVECs). Here, we explored the underlying mechanism of mitophagy induction. The ER stress induced by proteostasis failure in HUVECs promoted the Ca2+ transfer from ER to mitochondria, resulting in mitochondria Ca2+ overload, decreased mitochondrial membrane potential, mitochondria fission, and accumulation of Parkin and p62 in mitochondria and mitophagy under simulated microgravity. Moreover, we assumed that mitophagy played a vital role in functional changes in endothelial cells under simulated microgravity. Using mdivi-1 and PINK1 knockdown, we found that NLRP3 inflammasome activation was enhanced after mitophagy was inhibited. The NLRP3 inflammasome contributed to endothelial hyperpermeability and cellular migration by releasing IL-1ß. Thus, mitophagy inhibited cell migration ability and hyperpermeability in HUVECs exposed to clinostat-simulated microgravity. Collectively, we here clarify the mechanism of mitophagy induction by simulated microgravity in vitro and demonstrate the relationship between mitophagy and vascular endothelial functional changes including cellular migration and permeability. This study deepens the understanding of vascular functional changes under microgravity.

15.
Front Public Health ; 10: 922716, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36299766

RESUMO

Objective: Night shifts have adverse cognitive outcomes that might be attenuated by daytime napping. The neurovisceral integration model suggests that resting vagally mediated heart rate variability (vmHRV) is linked with cognitive function. This study investigated the relationship between resting vmHRV and cognitive function after different nap durations in interns after shift work. Methods: A total of 105 interns were randomly allocated to one of three groups (non-nap, n = 35; 15-min nap, n = 35; 45-min nap, n = 35) to perform cognitive tests and resting vmHRV at 12:00, 15:00 and 18:00. Information processing (digit symbol substitution test; DSST), motor speed (finger tapping test; FTT), response selection (choice reaction time; CRT), and attention shifts (shifting attention test; SAT) were assessed. Resting vmHRV was assessed at baseline and during each cognitive task across groups. Results: Compared with the non-nap control, the 15-min and 45-min naps improved all outcome measures (including subjective sleepiness and cognitive performance) at 15:00, with some benefits maintained at 18:00. The 15-min nap produced significantly greater benefits on the FTT at 15:00 after napping than did the 45-min nap. Resting vmHRV was significantly correlated with DSST and SAT performance. In addition, FTT performance was the only significant predictor of DSST performance across different nap durations. Conclusion: Our results demonstrate links between daytime napping (in particular, a 15-min nap) and improved cognitive control in relation to autonomic activity after shift work in interns. These results indicated that autonomic activity when awake plays a crucial role in DSST and SAT performance and facilitated the understanding of differences in neurocognitive mechanisms underlying information processing after different nap durations.


Assuntos
Privação do Sono , Tolerância ao Trabalho Programado , Humanos , Cognição , Sono/fisiologia , Vigília/fisiologia , Tolerância ao Trabalho Programado/fisiologia
16.
Cytokine ; 56(3): 648-55, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21962931

RESUMO

Cardiovascular and musculoskeletal deconditioning occurring in long-term spaceflight requires new strategies to counteract these adverse effects. We previously reported that a short-arm centrifuge produced artificial gravity (AG), together with ergometer, has an approving effect on promoting cardiovascular function. The current study sought to investigate whether the cardiac and cerebrovascular functions were maintained and improved using a strategy of AG combined with exercise training on cardiovascular function during 4-day head-down bed rest (HDBR). Twelve healthy male subjects were assigned to a control group (CONT, n=6) and an AG combined with ergometric exercise training group (CM, n=6). Simultaneously, cardiac pumping and systolic functions, cerebral blood flow were measured before, during, and after HDBR. The results showed that AG combined with ergometric exercise caused an increase trend of number of tolerance, however, there was no significant difference between the two groups. After 4-day HDBR in the CONT group, heart rate increased significantly (59±6 vs 66±7 beats/min), while stroke volume (98±12 vs 68±13 mL) and cardiac output (6±1 vs 4±1 L/min) decreased significantly (p<0.05). All subjects had similar drops on cerebral vascular function. Volume regulating hormone aldosterone increased in both groups (by 119.9% in CONT group and 112.8% in the CM group), but only in the CONT group there were a significant changes (p<0.05). Angiotensin II was significantly increased by 140.5% after 4-day HDBR in the CONT group (p<0.05), while no significant changes were observed in the CM group. These results indicated that artificial gravity with ergometric exercise successfully eliminated changes induced by simulated weightlessness in heart rate, volume regulating hormones, and cardiac pumping function and partially maintained cardiac systolic function. Hence, a daily 1h alternating +1.0 and +2.0 Gz with 40 W exercise training appear to be an effective countermeasure against cardiac deconditioning.


Assuntos
Repouso em Cama , Encéfalo/irrigação sanguínea , Encéfalo/fisiologia , Ergometria , Gravidade Alterada , Decúbito Inclinado com Rebaixamento da Cabeça/fisiologia , Coração/fisiologia , Aldosterona/sangue , Angiotensina II/sangue , Artérias/fisiologia , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/fisiologia , Peso Corporal/fisiologia , Circulação Cerebrovascular/fisiologia , Exercício Físico/fisiologia , Testes de Função Cardíaca , Frequência Cardíaca/fisiologia , Humanos , Masculino , Intolerância Ortostática/sangue , Intolerância Ortostática/fisiopatologia , Sístole/fisiologia , Fatores de Tempo , Adulto Jovem
17.
Eur J Appl Physiol ; 111(9): 2315-25, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21336952

RESUMO

We have shown previously that combined short-arm centrifuge and aerobic exercise training preserved several physiologically important cardiovascular functions in humans. We hypothesized that artificial gravity (AG) and exercise is effective to prevent changes of physical problems during head-down bed rest (HDBR). To test this hypothesis, 12 healthy male subjects had undergone 4 days of 6° HDBR. Six of them were exposed to AG of an alternating 2-min intervals of +1.0 and +2.0 Gz at foot level for 30 min twice per day with ergometric exercise of 40 W as a countermeasure during bed rest (CM group), while the remaining six served as untreated controls (no-CM group). Before and after 4 days of bed rest, leg venous hemodynamics was assessed by venous occlusion plethysmography and autonomic cardiovascular control estimated by power spectral analysis of blood pressure and heart rate. Further, orthostatic tolerance was evaluated by a 75° head-up tilt test and physical working capacity was surveyed by near maximal physical working capacity test before and after bed rest. The data showed that combined centrifuge and exercise applied twice daily for a total of 60 min during 4 days of HDBR prevented (a) a decrease in working capacity, (b) autonomic dysfunction (a decrease in the activity of parasympathetic cardiac innervation) and (c) an increase in leg venous flow resistance. The combination of a 30 min alternating of +1.0 and +2.0 Gz for twice per day of AG with 40 W ergometric exercise may offer a promising countermeasure to short duration simulated microgravity.


Assuntos
Repouso em Cama , Descondicionamento Cardiovascular , Exercício Físico/fisiologia , Gravidade Alterada , Decúbito Inclinado com Rebaixamento da Cabeça , Contramedidas de Ausência de Peso , Adulto , Repouso em Cama/efeitos adversos , Pressão Sanguínea/fisiologia , Descondicionamento Cardiovascular/fisiologia , Teste de Esforço , Gravidade Alterada/efeitos adversos , Decúbito Inclinado com Rebaixamento da Cabeça/efeitos adversos , Decúbito Inclinado com Rebaixamento da Cabeça/fisiologia , Frequência Cardíaca/fisiologia , Hemodinâmica , Humanos , Masculino , Fatores de Tempo , Simulação de Ausência de Peso/métodos , Adulto Jovem
18.
Med Sci Monit ; 16(12): CR575-83, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21119574

RESUMO

BACKGROUND: Musculoskeletal and cardiovascular deconditioning occurring in long-term spaceflight gives rise to the needs to develop new strategies to counteract these adverse effects. Short-arm centrifuge combined with ergometer has been proposed as a strategy to counteract adverse effects of microgravity. This study sought to investigate whether the combination of short-arm centrifuge and aerobic exercise training have advantages over short-arm centrifuge or aerobic exercise training alone. MATERIAL/METHODS: One week training was conducted by 24 healthy men. They were randomly divided into 3 groups: (1) short-arm centrifuge training, (2) aerobic exercise training, 40 W, and (3) combined short-arm centrifuge and aerobic exercise training. Before and after training, the cardiac pump function represented by stroke volume, cardiac output, left ventricular ejection time, and total peripheral resistance was evaluated. Variability of heart rate and systolic blood pressure were determined by spectral analysis. Physical working capacity was surveyed by near maximal physical working capacity test. RESULTS: The 1-week combined short-arm centrifuge and aerobic exercise training remarkably ameliorated the cardiac pump function and enhanced vasomotor sympathetic nerve modulation and improved physical working capacity by 10.9% (P<.05, n=8). In contrast, neither the short-arm centrifuge nor the aerobic exercise group showed improvements in these functions. CONCLUSIONS: These results demonstrate that combined short-arm centrifuge and aerobic exercise training has advantages over short-arm centrifuge or aerobic exercise training alone in influencing several physiologically important cardiovascular functions in humans. The combination of short-arm centrifuge and aerobic exercise offers a promising countermeasure to microgravity.


Assuntos
Exercício Físico/fisiologia , Hipogravidade , Análise de Variância , Pressão Sanguínea , Débito Cardíaco , Centrifugação , Frequência Cardíaca , Humanos , Masculino , Avaliação da Capacidade de Trabalho , Adulto Jovem
19.
Medicine (Baltimore) ; 99(23): e20252, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32501973

RESUMO

BACKGROUND: Bell palsy (BP) is a simple peripheral facial paralysis. A variety of acupuncture treatments have been reported effective for the recovery of BP. However, the relative effectiveness of these acupuncture treatments is still unclear. Therefore, we plan to summarize the evidence and determine the most effective acupuncture treatment for BP. METHODS: We will search the following database, including The Cochrane Library, PubMed, Web of Science, EMBASE, China BioMedical Literature (CBM),China National Knowledge Infrastructure (CNKI), Chinese Scientific Journals Database (VIP), and Wanfang database, from their inceptions to April 30, 2020, in order to collect randomized controlled trials (RCTs) on acupuncture in the treatment of BP. We will use Stata16.0 and WinBUGS software for statistical analysis and draw surface under the cumulative ranking curve (SUCRA) graph for each outcome indicator to predict the order of curative effect of treatment measures. RESULTS: This study will compare and rank the effectiveness of different acupuncture methods in the treatment of BP, and the outcome indicators will include House-Brackmann Grading Scale, sequelae, Facial Disability Index score, Sunnybrook facial grading system, Portmann score, and adverse events. CONCLUSION: Our study will provide supports for clinical practice.INPLASY registration number: INPLASY202040019.


Assuntos
Terapia por Acupuntura/métodos , Paralisia de Bell/terapia , Terapia por Acupuntura/efeitos adversos , Teorema de Bayes , Avaliação da Deficiência , Humanos , Metanálise em Rede , Ensaios Clínicos Controlados Aleatórios como Assunto , Recuperação de Função Fisiológica , Projetos de Pesquisa , Índice de Gravidade de Doença , Metanálise como Assunto
20.
J Cell Biochem ; 107(2): 357-63, 2009 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19306295

RESUMO

Alterations of nitric oxide contribute to post-flight orthostatic intolerance. The aim of this study was to investigate the changes of inducible nitric oxide synthase (iNOS) and the mechanisms underlying regulation of iNOS by simulated microgravity in human umbilical vein endothelial cells (HUVECs). Clinorotation, a simulated-model of microgravity, increased iNOS expression and promoter activity in HUVECs. The transactivations of NF-kappaB and AP-1 were suppressed by 24 h clinorotation. A key role for AP-1, but not NF-kappaB in the regulation of iNOS was shown. (1) PDTC, a NF-kappaB inhibitor, had no effect on clinorotation upregulation of iNOS. (2) SP600125, a JNK-specific inhibitor, which resulted in inhibition of AP-1 activity, enhanced the iNOS expression and promoter activity in clinorotation. (3) Overexpression of AP-1 remarkably attenuated the upregulation effect of clinorotation. These findings indicate that clinorotation upregulates iNOS in HUVECs by a mechanism dependent on suppression of AP-1, but not NF-kappaB. These results support a key role for AP-1 in the signaling of postflight orthostatic intolerance.


Assuntos
Células Endoteliais/metabolismo , Óxido Nítrico Sintase Tipo II/biossíntese , Intolerância Ortostática/fisiopatologia , Rotação/efeitos adversos , Fator de Transcrição AP-1/metabolismo , Western Blotting , Regulação para Baixo , Regulação Enzimológica da Expressão Gênica , Humanos , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Voo Espacial , Ativação Transcricional , Veias Umbilicais , Regulação para Cima , Simulação de Ausência de Peso
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